[Cranberry preparations in urological practice: view of a clinical pharmacologist]

Cranberry has been used in various urological problems from ancient times but only now cranberry preparations were studied clinically and pharmacologically in terms of prophylaxis of urinary tract infections. The active component of cranberry are protoantocianides which have no antibacterial activity but inhibit adhesion of uropathogenic E.coli due to block of P-fimbria and thus inhibit development of biofilms. When cranberry preparations are taken per os, proantocianides accumulate in high doses in urine. Efficacy of cranberry in prophylaxis of recurrent urinary infection was demonstrated in randomized clinical trials. Administration of standard cranberry preparations containing not less than 36 mg of proantocianides such as monurel is recommended by European Urological Association (EUA). Cranberry preparations are well tolerated, especially in capsules. However, they can contribute to nephrolithiasis progression and enhance anticoagulation action of indirect anticoagulant drugs.